Optimizing plastics recycling networks

Plastic pollution is a serious sustainability issue facing the global community. Fragments of macroplastics and microplastics pollute terrestrial and aquatic ecosystems, while nanoplastics can also degrade air quality. The recent COVID-19 pandemic also exacerbated the problem. Large-scale commercial use of plastics recycling technologies is hindered by various socio-economic barriers. In particular, cross-contamination of mixed plastic streams is prevalent due to imperfect waste segregation. The concept of Plastics Recycling Networks is introduced to facilitate planning of reverse supply chains using optimization models. In this work, basic Linear Programming and Mixed-Integer Linear Programming models are developed for matching sources of waste plastic with plastic recycling plants within Plastics Recycling Networks. These models allocate streams while considering the ability of recycling plants to tolerate contaminants. Two illustrative case studies are analyzed to demonstrate the effectiveness of the models, and policy implications for mitigation of plastic pollution are discussed. These models enable planning of networks with some tolerance for contaminants in plastic waste, and can be the basis for developing new variants to handle additional real world aspects.

Blockchain technology for agricultural supply chains during the COVID-19 pandemic: Benefits and cleaner solutions.

This study aims to investigate blockchain technology for agricultural supply chains during the COVID-19 pandemic. Benefits and solutions are identified for the smooth conduction of agricultural supply chains during COVID-19 using blockchain. This study uses interviews with agricultural companies operating in Pakistan. The findings discover the seven most commonly shared benefits of applying blockchain technology, four major challenges, and promising solutions. About 100% of the respondents mentioned blockchain as a solution for tracking the shipment during COVID-19, data retrieval and data management, product and transaction frauds, and an Inflexible international supply chain. Roughly 75% of the respondents mentioned the challenge of lack of data retrieval and data management and the Inflexible international supply chain in COVID-19 besides their solutions. This study can expand existing knowledge related to agricultural supply chains. The experiences shared in this study can serve as lessons for practitioners to adopt the blockchain technology for performing agricultural supply chain during pandemic situations such as COVID-19.

How sustainable are the biodegradable medical gowns via environmental and social life cycle assessment?

The growing disposable medical gown consumption due to the COVID-19 pandemic has driven tons of waste to landfills and posed plastic pollution. Investigating the pros and cons of biodegradable gowns over conventional counterparts can guide disposable medical gowns to be environmentally and socially sustainable. This work presents environmental and social life cycle assessments (E− and S-LCA) of biodegradable gowns to compare their environmental and social performances with conventional ones. The E-LCA evaluates the full-spectrum environmental impacts from gown production to end-of-life waste management processes, while the S-LCA assesses their associated influence on economic growth, employment, and worker welfare. The social impacts are evaluated based on the economic input-output analysis results of the economic sectors or gown life cycle stages involved in the gown value chain. Results show that biodegradable gown production poses 10.76% higher ecotoxicity than conventional alternatives contributed by pro-oxidant manufacturing. Integrating the landfill gas (LFG) capture and utilization processes into biodegradable gown waste treatment can reduce 48.81% of life cycle land use and over 5.67% of total greenhouse gas emissions. However, integrating this process in sanitary landfills to treat disinfected gown wastes can increase technical complexity, which enhances 70% of safety risks and 40% frequency of forced labor. Industrial composting biodegradable gowns can reduce over 20.5% of particulate matter formation versus sanitary landfills. Overall, fossil-based gowns possess full-spectrum environmental and social advantages over biodegradable counterparts treated by industrial composting and sanitary landfills. If improving the efficiencies of LFG capture by 85%, biogenic methane oxidation by 43%, and heat generation by 85%, biodegradable gowns can outperform conventional counterparts in reducing GHG emissions and fossil fuel use.

Energy-saving COVID-19 biomedical plastic waste treatment using the thermal - Catalytic pyrolysis.

The rate of Biomedical waste generation increases exponentially during infectious diseases, such as the SARS-CoV-2 virus, which burst in December 2019 and spread worldwide in a very short time, causing over 6 M casualties worldwide till May 2022. As per the WHO guidelines, the facemask has been used by every person to prevent the infection of the SARS-CoV-2 virus and discarded as biomedical waste. In the present work, a 3-ply facemask was chosen to be treated using the solvent, which was extracted from the different types of waste plastics through the thermal-catalytic pyrolysis process using a novel catalyst. The facemask was dispersed in the solvent in a heating process, followed by dissolution and precipitation of the facemask in the solvent and by filtration of the solid facemask residue out of the solvent. The effect of peak temperature, heating rate, and type of solvent is observed experimentally, and it found that the facemask was dissolved completely with a clear supernate in the solvent extracted from the (polypropylene + poly-ethylene) plastic also saved energy, while the solvent from ABS plastic was not capable to dissolute the facemask. The potential of the presented approach on the global level is also examined.

Stakeholders' Impact Factors of the COVID-19 Pandemic on Sustainable Mixed Development Projects: A Systematic Review and Meta-Analysis

Managing stakeholders in construction projects is crucial since stakeholders are perceived as a significant source of uncertainty because of the various stakeholders involved, especially in mixed development projects. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) method was used to analyse and select the most relevant publications from two identified databases: SCOPUS and Web of Science (WoS). Only 55 of 1600 publications were identified as relevant to stakeholder impact factors in the construction projects. Towards achieving the Sustainable Development Goal (SDG) 11, 10 stakeholder impact factors affecting the success of mixed development project management during the COVID-19 pandemic were identified and arranged by frequency: stakeholder engagement, stakeholder relationship, stakeholder attribute, stakeholder influence, stakeholder interest, stakeholder needs, stakeholder satisfaction, stakeholder expectation, and stakeholder behaviour. The outcome of this study would assist the construction project team in effectively managing and engaging with the relevant stakeholders to attain SDG 11 associated with sustainable cities and communities, specifically for the mixed development projects during the COVID-19 pandemic.

Critical role of Hyssop plant in the possible transmission of SARS-CoV-2 in contaminated human Feces and its implications for the prevention of the virus spread in sewage.

The significant issue affecting wastewater treatment is human faeces containing SARS-CoV-2. SARS-CoV-2, as a novel coronavirus, has expanded globally. While the current focus on the COVID-19 epidemic is rightly on preventing direct transmission, the risk of secondary transmission via wastewater should not be overlooked. Many researchers have demonstrated various methods and tools for preventing and declining this virus in wastewater treatment, especially for SARS-CoV-2 in human faeces. This research reports two people tested for 30 d, with written consent, at Mosa-Ebne-Jafar Hospital of Quchan, Iran, from September 1st to October 9th, 2021. The two people's conditions are the same. The Hyssop plant was used, which boosts the immune system's effectiveness and limonene, rosemary, caffeic acids and flavonoids, all biologically active compounds in this plant, cause improved breathing problems, colds, and especially for SARS-CoV-2. As a result, utilising the Hyssop plant can help in reducing SARS-CoV-2 in faeces. This plant's antioxidant properties effectively reduce SARS-CoV-2 in faeces by 30%; nevertheless, depending on the patient's condition. This plant is also beneficial for respiratory and digestive health.

Sustainable development in period of COVID-19 pandemic.

COVID-19 pandemic has shown that sustainable development of energy, water and environment systems is essential for the basic life needs of humankind. Logistics problems, shortage of resources and goods, a crisis of traditional energy systems, all these COVID-19 caused problems show that available resources should be used with caution. This paper is an introduction article to the Virtual Special Issue that discusses some of the latest developments in three research topic areas, namely Energy, Water and Environment. These research topics emerged from the four Sustainable Development of Energy, Water and Environment Systems Conferences held in 2020. The purpose of the introduction article is to provide a brief introduction to the field and the articles included in this Journal of Cleaner Production Virtual Special Issue.

To what extent waste management strategies need adaptation to post-COVID-19

The world has been grappling with the crisis of the COVID-19 pandemic for more than a year. Various sectors have been affected by COVID-19 and its consequences. The waste management system is one of the sectors affected by such unpredictable pandemics. The experience of COVID-19 proved that adaptability to such pandemics and the post-pandemic era had become a necessity in waste management systems and this requires an accurate understanding of the challenges that have been arising. The accurate information and data from most countries severely affected by the pandemic are not still available to identify the key challenges during and post-COVID-19. The documented evidence from literature has been collected and the attempt has been made to summarise the arising challenges and the lessons learned. This review covers all raised challenges concerning the various aspects of the waste management system from generation to final disposal (i.e., generation, storage, collection, transportation, processing, and burial of waste). The necessities and opportunities are recognized for increasing flexibility and adaptability in waste management systems. The four basic pillars are enumerated to adapt the waste management system to the COVID-19 pandemic and post-COVID-19 conditions. Striving to support and implement a circular economy is one of its basic strategies. Graphical Unlabelled Image

Changes in water use and wastewater generation influenced by the COVID-19 pandemic: A case study of China.

This paper examines and projects the water use and wastewater generation during and after the SARS-CoV-2 (COVID-19) in China, and discussed the water use/wastewater generation pattern changes among different sectors. Existing studies on the impact of pandemic spread-prevention measures on water consumption and wastewater treatment during the pandemic are reviewed. The water use and wastewater discharge in China through the COVID-19 period are then projected and analyzed using Multivariate Linear Regression. The projection is carried out for years 2019-2023 and covers an (estimated) full process of pre-pandemic, pandemic outbreak, and recovery phase and provides essential information for determining the complete phase impact of the COVID-19. Two scenarios, i.e. the recovery scenario and the business as usual scenario, are set to investigate the water use and wastewater generation characteristics after the pandemic. The results imply that in both scenarios, the water use in China shows a V-shaped trend from 2019 to 2023 and reached a low point in 2020 of 5,813✕108 m3. The wastewater discharge shows an increasing trend throughout the COVID period in both scenarios. The results are also compared with the water consumption and wastewater generation during the SARS-CoV-1 period. The implication for policymakers is the possible increase of water use and wastewater discharge in the post COVID period and the necessity to ensure the water supply and control of water pollution and wastewater discharge.

Modeling Residential Electricity Consumption from Public Demographic Data for Sustainable Cities

Demographic factors, statistical information, and technological innovation are prominent factors shaping energy transitions in the residential sector. Explaining these energy transitions requires combining insights from the disciplines investigating these factors. The existing literature is not consistent in identifying these factors, nor in proposing how they can be combined. In this paper, three contributions are made by combining the key demographic factors of households to estimate household energy consumption. Firstly, a mathematical formula is developed by considering the demographic determinants that influence energy consumption, such as the number of persons per household, median age, occupancy rate, households with children, and number of bedrooms per household. Secondly, a geographical position algorithm is proposed to identify the geographical locations of households. Thirdly, the derived formula is validated by collecting demographic factors of five statistical regions from local government databases, and then compared with the electricity consumption benchmarks provided by the energy regulators. The practical feasibility of the method is demonstrated by comparing the estimated energy consumption values with the electricity consumption benchmarks provided by energy regulators. The comparison results indicate that the error between the benchmark and estimated values for the five different regions is less than 8% (7.37%), proving the efficacy of this method in energy consumption estimation processes.

Unprecedented Impacts of Aviation Emissions on Global Environmental and Climate Change Scenario.

There has been a continuously growing trend in international commercial air traffic, with the exception of COVID-19 crises; however, after the recovery, the trend is expected to even sharpen. The consequences of released emissions and by-products in the environment range from human health hazards, low air quality and global warming. This study is aimed to investigate the role of aviation emissions in global warming. For this purpose, data on different variables including global air traffic and growth rate, air traffic in different continents, total global CO2 emissions of different airlines, direct and indirect emissions, air traffic in various UK airports and fuel-efficient aircraft was collected from various sources like EU member states, Statista, Eurostat, IATA, CAA and EUROCONTROL. The results indicated that in 2019, commercial airlines carried over 4.5 × 109 passengers on scheduled flights. However, due to the COVID-19 pandemic in 2020, the global number of passengers was reduced to 1.8 × 109, representing around a 60% reduction in air traffic. Germany was the largest contributor to greenhouse gas (GHG) from the EU, releasing 927 kt of emissions in 3 years. In the UK, Heathrow airport had the highest number of passengers in 2019 with over 80 million, and the study of monthly aircraft movement revealed that Heathrow Airport also had the highest number of EU and International flights, while Edinburgh had the domestic flights in 2018. These research findings could be beneficial for airlines, policymakers and governments targeting the reduction of aircraft emissions.

Cleaner technologies for sustainable development

Anthropogenic influence on global warming is now undeniably proven scientific fact. Ever-increasing efforts directed towards cleaner technologies are needed given the fact that COVID-19 caused disturbances in global supply chains, and a record increase in natural gas No table of figures entries found.prices led to coal power production revitalization, nuclear renaissance and overall hampering of the energy transition. Cleaner technologies are becoming increasingly important on our path towards sustainable development. Present work builds on contributions from this special issue dedicated to the four Sustainable Development of Energy, Water and Environment Systems Conferences held in 2020 by emphasizing the role of cleaner technologies and detecting research trends. By dissecting recent examples of cleaner technologies in environmental systems, water systems and industrial processes, circular economy principles are obeyed through the application of cleaner technologies, where the material and energy loops are closed through cross-sectoral integration. Digitalization and advanced control concepts are expected to accelerate that integration under the smart paradigm. As technology for decarbonization is maturing and becoming increasingly compatible with the market, the focus is placed more on the social dimension of sustainability.

Integration and optimisation for sustainable industrial processing within the circular economy

This Virtual Special Issue (VSI) contains some of the papers presented at the 23rd Conference of Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction (PRES′20), which was virtually held in Xi'an, China on the 17 to 21 August 2020, related to the scope of Renewable and Sustainable Energy Reviews. The works are not limited to review articles;most of them have significant contributions to knowledge development for integration and optimisation for sustainable industrial processing within the circular economy. Topics covered in this VSI also includes studies on salt hydrate-based gas-solid thermochemical energy storage technology, hybrid battery optimisation, and energy recovery under thermal waste-to-energy. In addition, work on novel and effective passive cooling strategy for photovoltaic panels, integrated gasification combined cycle (IGCC) power generation systems, heat pumps optimisation in low-temperature waste heat recovery, utilisation of solar heating systems for low-temperature heat demand industries, and double reheat for thermal power generation are presented. The articles on the energy strategies towards the circular economy (CE) show the content of biomass supply chain optimisation, renewable energy system towards carbon emissions neutral, stable energy use strategies. Lastly, nexus thinking for sustainable development under COVID-19 assesses the energy and environmental performance of waste personal protective equipment treatment and the optimisation of the energy-water-waste nexus at the district level for regional sustainability. These achievements communicate the most significant and relevant critical thinking in renewable and sustainable energy research and development.

Trend towards virtual and hybrid conferences may be an effective climate change mitigation strategy.

Since 2020, the COVID-19 pandemic has urged event holders to shift conferences online. Virtual and hybrid conferences are greener alternatives to in-person conferences, yet their environmental sustainability has not been fully assessed. Considering food, accommodation, preparation, execution, information and communication technology, and transportation, here we report comparative life cycle assessment results of in-person, virtual, and hybrid conferences and consider carbon footprint trade-offs between in-person participation and hybrid conferences. We find that transitioning from in-person to virtual conferencing can substantially reduce the carbon footprint by 94% and energy use by 90%. For the sake of maintaining more than 50% of in-person participation, carefully selected hubs for hybrid conferences have the potential to slash carbon footprint and energy use by two-thirds. Furthermore, switching the dietary type of future conferences to plant-based diets and improving energy efficiencies of the information and communication technology sector can further reduce the carbon footprint of virtual conferences.

Planning of a Flexible Refined Products Transportation Network in Response to Emergencies

The stable supply of refined products is a vital measure to maintain national security and economic development. However, unexpected accidents and incidents, such as pipeline failures, natural hazards, and even this Covid-19 period can disrupt the supply of refined products to the end-users, leading to shortages on the demand side. This issue should be considered in advance in the planning process to increase transportation flexibility. In this paper, a MILP model-based method is proposed to increase the operational flexibility of refined products transportation. This model takes into account several failure conditions of routes during the transportation process and determines the backup transport route plan. The illustration case study demonstrates how to build a more flexible refined products transportation process through expanding transport and sending capacities to satisfy the demand for refined products in market depots. The results show that the capacity expansion plans are different when disruptions are individually and simultaneously considered, a 33.60 % difference in the expansion cost. The proposed method could be helpful to ensure the supply of retail markets when facing emergencies.

Post COVID-19 ENERGY sustainability and carbon emissions neutrality.

This review covers the recent advancements in selected emerging energy sectors, emphasising carbon emission neutrality and energy sustainability in the post-COVID-19 era. It benefited from the latest development reported in the Virtual Special Issue of ENERGY dedicated to the 6th International Conference on Low Carbon Asia and Beyond (ICLCA'20) and the 4th Sustainable Process Integration Laboratory Scientific Conference (SPIL'20). As nations bind together to tackle global climate change, one of the urgent needs is the energy sector's transition from fossil-fuel reliant to a more sustainable carbon-free solution. Recent progress shows that advancement in energy efficiency modelling of components and energy systems has greatly facilitated the development of more complex and efficient energy systems. The scope of energy system modelling can be based on temporal, spatial and technical resolutions. The emergence of novel materials such as MXene, metal-organic framework and flexible phase change materials have shown promising energy conversion efficiency. The integration of the internet of things (IoT) with an energy storage system and renewable energy supplies has led to the development of a smart energy system that effectively connects the power producer and end-users, thereby allowing more efficient management of energy flow and consumption. The future smart energy system has been redefined to include all energy sectors via a cross-sectoral integration approach, paving the way for the greater utilization of renewable energy. This review highlights that energy system efficiency and sustainability can be improved via innovations in smart energy systems, novel energy materials and low carbon technologies. Their impacts on the environment, resource availability and social well-being need to be holistically considered and supported by diverse solutions, in alignment with the sustainable development goal of Affordable and Clean Energy (SDG 7) and other related SDGs (1, 8, 9, 11,13,15 and 17), as put forth by the United Nations.

Time series forecasting of new cases and new deaths rate for COVID-19 using deep learning methods.

The first known case of Coronavirus disease 2019 (COVID-19) was identified in December 2019. It has spread worldwide, leading to an ongoing pandemic, imposed restrictions and costs to many countries. Predicting the number of new cases and deaths during this period can be a useful step in predicting the costs and facilities required in the future. The purpose of this study is to predict new cases and deaths rate one, three and seven-day ahead during the next 100 days. The motivation for predicting every n days (instead of just every day) is the investigation of the possibility of computational cost reduction and still achieving reasonable performance. Such a scenario may be encountered in real-time forecasting of time series. Six different deep learning methods are examined on the data adopted from the WHO website. Three methods are LSTM, Convolutional LSTM, and GRU. The bidirectional extension is then considered for each method to forecast the rate of new cases and new deaths in Australia and Iran countries. This study is novel as it carries out a comprehensive evaluation of the aforementioned three deep learning methods and their bidirectional extensions to perform prediction on COVID-19 new cases and new death rate time series. To the best of our knowledge, this is the first time that Bi-GRU and Bi-Conv-LSTM models are used for prediction on COVID-19 new cases and new deaths time series. The evaluation of the methods is presented in the form of graphs and Friedman statistical test. The results show that the bidirectional models have lower errors than other models. A several error evaluation metrics are presented to compare all models, and finally, the superiority of bidirectional methods is determined. This research could be useful for organisations working against COVID-19 and determining their long-term plans.

Energy and environmental sustainability of waste personal protective equipment (PPE) treatment under COVID-19.

Combating the COVID-19 pandemic has raised the demand for and disposal of personal protective equipment in the United States. This work proposes a novel waste personal protective equipment processing system that enables energy recovery through producing renewable fuels and other basic chemicals. Exergy analysis and environmental assessment through a detailed life cycle assessment approach are performed to evaluate the energy and environmental sustainability of the processing system. Given the environmental advantages in reducing 35.42% of total greenhouse gas emissions from the conventional incineration and 43.50% of total fossil fuel use from landfilling processes, the optimal number, sizes, and locations of establishing facilities within the proposed personal protective equipment processing system in New York State are then determined by an optimization-based site selection methodology, proposing to build two pre-processing facilities in New York County and Suffolk County and one integrated fast pyrolysis plant in Rockland County. Their optimal annual treatment capacities are 1,708 t/y, 8,000 t/y, and 9,028 t/y. The proposed optimal personal protective equipment processing system reduces 31.5% of total fossil fuel use and 35.04% of total greenhouse gas emissions compared to the personal protective equipment incineration process. It also avoids 41.52% and 47.64% of total natural land occupation from the personal protective equipment landfilling and incineration processes.

COVID-19 pandemics Stage II - Energy and environmental impacts of vaccination.

The COVID-19 pandemic developed the severest public health event in recent history. The first stage for defence has already been documented. This paper moves forward to contribute to the second stage for offensive by assessing the energy and environmental impacts related to vaccination. The vaccination campaign is a multidisciplinary topic incorporating policies, population behaviour, planning, manufacturing, materials supporting, cold-chain logistics and waste treatment. The vaccination for pandemic control in the current phase is prioritised over other decisions, including energy and environmental issues. This study documents that vaccination should be implemented in maximum sustainable ways. The energy and related emissions of a single vaccination are not massive; however, the vast numbers related to the worldwide production, logistics, disinfection, implementation and waste treatment are reaching significant figures. The preliminary assessment indicates that the energy is at the scale of ~1.08 × 1010 kWh and related emissions of ~5.13 × 1012 gCO2eq when embedding for the envisaged 1.56 × 1010 vaccine doses. The cold supply chain is estimated to constitute 69.8% of energy consumption of the vaccination life cycle, with an interval of 26-99% depending on haul distance. A sustainable supply chain model that responds to an emergency arrangement, considering equality as well, should be emphasised to mitigate vaccination's environmental footprint. This effort plays a critical role in preparing for future pandemics, both environmentally and socially. Research in exploring sustainable single-use or reusable materials is also suggested to be a part of the plans. Diversified options could offer higher flexibility in mitigating environmental footprint even during the emergency and minimise the potential impact of material disruption or dependency.

Energy, environmental, economic and social equity (4E) pressures of COVID-19 vaccination mismanagement: A global perspective.

Vaccination now offers a way to resolve the COVID-19 pandemic. However, it is critical to recognise the full energy, environmental, economic and social equity (4E) impacts of the vaccination life cycle. The full 4E impacts include the design and trials, order management, material preparation, manufacturing, cold chain logistics, low-temperature storage, crowd management and end-of-life waste management. A life cycle perspective is necessary for sustainable vaccination management because a prolonged immunisation campaign for COVID-19 is likely. The impacts are geographically dispersed across sectors and regions, creating real and virtual 4E footprints that occur at different timescales. Decision-makers in industry and governments have to act, unify, resolve, and work together to implement more sustainable COVID-19 vaccination management globally and locally to minimise the 4E footprints. Potential practices include using renewable energy in production, storage, transportation and waste treatment, using better product design for packaging, using the Internet of Things (IoT) and big data analytics for better logistics, using real-time database management for better tracking of deliveries and public vaccination programmes, and using coordination platforms for more equitable vaccine access. These practices raise global challenges but suggest solutions with a 4E perspective, which could mitigate the impacts of global vaccination campaigns and prepare sustainably for future pandemics and global warming.